Pregnancy complications in mothers with high blood pressure are linked to poorer cardiovascular health in their children more than two decades later, according to a new study that adds to mounting evidence that heart disease risk can be passed across generations.
The research, led by scientists at Northwestern Medicine and published in JAMA Network Open, evaluated nearly 1,350 mother-child pairs from birth until the children reached around 22 years of age, using data originally collected between 1998 and 2000 across 20 cities in the United States.
Researchers identified whether mothers experienced pregnancy complications from hospital records and then analysed the children’s cardiovascular health through blood pressure readings, blood tests, body mass index (BMI) assessments and arterial ultrasounds. They compared children who were and were not exposed to each complication, accounting for potential contributing factors such as smoking and lifestyle.
Early signs of arterial ageing
Children whose mothers had high blood pressure during pregnancy — known medically as hypertensive disorders of pregnancy (HDP) — showed a cluster of worrying health markers. They had higher BMI, higher blood sugar levels (elevated HbA1c), higher blood pressure and thicker artery walls. Their arteries appeared three to five years older than their chronological age, a sign of early arterial injury that raises the risk of future heart disease.
The study also examined other pregnancy complications. Exposure to gestational diabetes was linked to worse blood pressure and some evidence of artery thickening, while preterm birth was associated with higher blood sugar levels in the offspring.
High blood pressure disorders affect between 5 and 10 per cent of women during pregnancy in the United States, and cases have increased by 25 per cent over the past 20 years, according to the U.S. Centers for Disease Control and Prevention (CDC). Broader data cited in the research indicate that hypertensive disorders of pregnancy affect around 15 per cent of women during their reproductive years. In the U.S., the prevalence of HDP among delivery hospitalisations rose from 13.3 per cent to 15.9 per cent between 2017 and 2019. Another study recorded an increase from 2.8 per cent in 1989 to 8.2 per cent in 2020. Chronic hypertension in pregnancy has doubled in the U.S. from 2007 to 2021. Contributing factors include advanced maternal age, rising obesity rates and other cardiometabolic risks. Significant racial and ethnic disparities exist, with the highest rates of HDP seen among Black women and American Indian or Alaska Native women.
Intergenerational transmission of risk
The findings reinforce a growing understanding that cardiovascular risk can be transmitted from mother to child through a combination of biological, environmental and behavioural factors. Other research supports this picture. A previous Northwestern Medicine and Lurie Children’s Hospital study found that over 90 per cent of U.S. mothers have suboptimal cardiovascular health during pregnancy, suggesting their children may be at higher risk for early declines in their own heart health. An investigation from the Keck School of Medicine of USC linked maternal obesity, gestational diabetes and hypertensive disorders to elevated blood pressure in offspring, with effects that grow as children age and that are more pronounced in female and Black children. A Mayo Clinic study found that babies exposed to hypertension in the womb had a significantly increased risk of developing chronic hypertension later in life. A UK study analysing health records of women in England found that those with high blood pressure during pregnancy, especially with complications, had twice the risk of cardiovascular disease compared to women with normal blood pressure and no complications.
Cardiovascular disease remains the leading cause of death globally, accounting for 19.2 million deaths in 2023. In the U.S., it caused nearly 920,000 deaths in 2023, with coronary artery disease responsible for more than a third of those. While mortality from CVD declined in the U.S. in 2023 compared with previous years, it has been increasing since 2010, largely driven by rising obesity, diabetes and hypertension.
Prevention starts with lifestyle
Fortunately, high blood pressure and heart disease risk are factors that people can influence — and even reverse — through diet, exercise, sleep and avoiding harmful substances. The CDC recommends that American adults get at least seven hours of sleep each night and at least 150 minutes of exercise each week for optimal health. These behaviours are learned from an early age and begin with parents.
Dr Nilay Shah, assistant professor of medicine at Northwestern University Feinberg School of Medicine and a senior author of the study, said in a statement: “If you experienced high blood pressure or high blood sugar during pregnancy, or your child was born early, it does not absolutely mean that your child will have worse health as adults. But I would encourage you to pay attention now to your child’s health behaviours.”
In the United States, hypertensive disorders of pregnancy increased from 2.8 per cent in 1989 to 8.2 per cent in 2020.